OK, I understand that the best way to get more car is to trade the 328 in for a 335, but that's not really an option right now.

Bavarian Auto sells Scorpion and Remus muffler kits for my car and am interested in opinions on these or other aftermarket products that I could install that provide tangible improvements.

I'm primarily interested in changing the exhaust because I want a better sound and have heard that other options, such as replacing the air intake, don't make much of a difference.

Thanks!

You've pretty much heard right. An exhaust won't make much difference either, except for the sound (which you're upfront about - no problem with that). Don't be offended for me asking, but have you done any 'CCA HPDEs (or similar training)? If not, that's one great way to get more from your car - or any car you drive.

Don't be offended for me asking, but have you done any 'CCA HPDEs (or similar training)? If not, that's one great way to get more from your car - or any car you drive.

Excellent point. I have been through a driving course at Bill Scott Racing and also a one day 'refresher course' through Crucible. However, to get more to your point, I haven't been through a CCA HPDE nor have I used my car in any autocross events (not that I wouldn't or aren't interested, I just haven't...yet).

Perhaps a description of my driving style will be helpful. I don't drag race on a green light or floor the pedal from stop signs, but do seem to accelerate a bit quicker than most. I don't exceed the speed limit (much) or weave through traffic and spend most of my time driving with the flow. However, when it comes to turns I like to hear feedback from my tires. Maybe I should be focusing more on suspension improvements or sway bars...

+1 to everyone who promotes HPDE as a way of getting more out of your car.

Another alternative would be to get an E30 (1984-1991) 325i or a 1990 or 1991 318is as an HPDE car. Less weight, fewer electronic distractions than your E9x. Best bet is a 5-speed manual car. E28's (1982 to 1988) 5-series also make great HPDE cars.

Best of all, both cars are bone simple to work on and modify.

Please check out my new science fiction adventure story now online at http://www.xybears.com. Your help and support with this would be greatly appreciated! Thank you!

Another alternative would be to get an E30 (1984-1991) 325i or a 1990 or 1991 318is as an HPDE car. Less weight, fewer electronic distractions than your E9x. Best bet is a 5-speed manual car.

Yes, if you can find one! It looks to me like the E30 market is polarizing - at one end, you have the 'clean' E30's, going for some few thousands - $3k-$5k (and not all that many of those), and most of the rest going for not much money, but in reality, needing lots of work, that could easily add up to $2k or more; and then there's finding examples not besotted w/ rust - certainly easier in the non-rust-belt regions of the country, but lot of good that does if you're north or east, or anyplace that uses salt on roadways in winter. Lots of automatics out there, but 5-spds. are available.

bcweir said:

E28's (1982 to 1988) 5-series also make great HPDE cars.
Best of all, both cars are bone simple to work on and modify.

Not sure if there's a plethora of good E28's out there and available, but yes, should be fine, the less rust the better. Slightly more complex front suspension design, but also possibly more serviceable compared to the E30's 'replace the whole control arm' instead of just a ball joint.

For a more recent option, I think there's lots & lots of E36's out there, reasonably clean and serviceable, for very little money. Of course, E36's have their own issues and foibles which likely need addressing by now, as well.

However, you didn't say anything about wanting another vehicle as a track toy - you might try some auto-x and a club driver's school or two in stock form, see more in that type of driving what you have, and then set goals, a budget, and a plan to get to where you want. There's plenty to be had out of your current vehicle before hopping into something else or upping the ante on your own bimmer, so starting w/ club schools and/or auto-x is a good place to start!

However, you didn't say anything about wanting another vehicle as a track toy - you might try some auto-x and a club driver's school or two in stock form, see more in that type of driving what you have, and then set goals, a budget, and a plan to get to where you want. There's plenty to be had out of your current vehicle before hopping into something else or upping the ante on your own bimmer, so starting w/ club schools and/or auto-x is a good place to start!

Excellent advice. No doubt there is more overall performance to be gained through experience and growing my own talent around the car I have as opposed to modifications that create even more unused mechanical capability.

Not much out there for the N52 engine. The tuners have focused on the N54/N55.

Exhaust and intake maybe give a few peak HP. BMW has been consistently efficient with the (stock) breathing of their engines.

However, either exhaust or intake "upgrades" will change the sound, so if that is what you are going for, it should work =)

HERE HERE!
Too many people buy cheap after market upgrades which have little to no effect on the cars performance. If BMW thought a different exhaust or intake would be better for the car they would make it themselves. Don't fall into the gimmick of putting monkey parts on your finely tuned performance automobile. If you want upgrades, get them from bimmer or Active Autowerks. AA works closely with BMW Power in Germany and those are the only names I trust. You pay hundreds for exhausts that only change the sound and perform worse under certain weather conditions and I've seen people pay a couple thousand for a dinan intake that only drops the weight of the car and performs worse than the stock when it's hot outside. I've gotten better results with a stock K&N filter charger than you can get with a 2k dinan intake upgrade. It's just not worth it.

BMW does make performance intake and exhaust for the 2007 328i. They don't add much power.
These accessories can be found on BMWUSA.com.

The BMW Performance exhaust system invigorates engine output by allowing engine by-products to exit the vehicle more efficiently. RPM performance is heightened and engine performance is increased by up to 5hp and 3 ft-lbs of torque at 6600 RPM, but there's also another benefit. As RPMs escalate, so does the exhaust note, creating a racy but never intrusive sound. (PN: 18 10 2 147 799)

Upgrading to a BMW Performance air intake system will unleash gains of up to 3 horsepower and 3 ft-lbs. of torque for your 3 Series, while also helping the engine to operate more efficiently with a 30% reduction in back pressure and increased overall performance. (PN: 13 72 0 444 751)

I have seen one dyno run from an E46 that showed 6 HP gain from just the Intake.

BMW does make performance intake and exhaust for the 2007 328i. They don't add much power.
These accessories can be found on BMWUSA.com.

The BMW Performance exhaust system invigorates engine output by allowing engine by-products to exit the vehicle more efficiently. RPM performance is heightened and engine performance is increased by up to 5hp and 3 ft-lbs of torque at 6600 RPM, but there's also another benefit. As RPMs escalate, so does the exhaust note, creating a racy but never intrusive sound. (PN: 18 10 2 147 799)

Upgrading to a BMW Performance air intake system will unleash gains of up to 3 horsepower and 3 ft-lbs. of torque for your 3 Series, while also helping the engine to operate more efficiently with a 30% reduction in back pressure and increased overall performance. (PN: 13 72 0 444 751)

I have seen one dyno run from an E46 that showed 6 HP gain from just the Intake.

These are all true, but I have dyno'd 8hp gains with a stock K&N filter replacement.... just do some research, because they are already pretty close to perfect.

You will spend hundreds or thousands, just like was said, for "MODEST" gains.

People like the 335 because the engine and turbos have lots of play room. The M3 is already tuned so far out you pay big bucks for "modest gains", and the 328 doesn't have the starting point you need so major bucks are required to get it anywhere near the 335.

The 335 can easily take an M3 and M5 (through 4th gear anyways)with minor turbo work. The stock turbos run at 7psi and mods can double this, giving you 14.5psi per turbo and 420bhp from Active autowerks. Call them and check it out. It all safe for your vehicle and doesn't void any warranty or cause any harm to the suspension or drivetrain.

Just call AA in Germany, I have heard of bad results from American retailers claiming to be working with the real AA. AA is who helps BMW Power at Nurburgring with mods and testing.

I have the BMW perfomance exhaust on my CPO 335i. I'm not sure I would have spent the money on that. The sound is nice, but I don't think it is worth the money. My wife once called me on my cell phone to say that something was wrong with the home furnace when she heard me crank the car 100 feet from the house. She doesn't care for the exhaust.

I just bought the BMW Performance Exhaust for my 328i coupe this week and absolutely love it and recommend it. Since the alleged performance gains are way up in the rev range and I rarely venture to 6.6k rpm, I doubt I will ever see any measurable performance benefit. I can however report awesome sound and throttle response is quicker. You also get some very nice welded chrome tips and did I mention the sound...

...then you haven't been paying attention to the rest of the threads on this post.

How about improving the NUT BEHIND THE WHEEL first? Just a thought. I just might be the guy in the left lane trying to get the hell out of your way before you ram your vehicle up my exhaust system.

If you can't master 230 hp on an HPDE course, you most certainly are not ready for three or four hundred.

Most naturally aspirated BMW's today are already running between 9 and 11 CR's. That's too much compression to be running any kind of boost on a street vehicle. Not only are you going to have to run premium fuel forever, but you're either going to be pinging that poor engine to the moon if you haven't blown it up already.

Mike Miller posted the best response to a Ronnie Ramjet that strapped a supercharger to his E46 M3 and has pretty much killed the block.

I have yet to see why a 328 NEEDS a supercharger. Isn't that why people buy a 335 or an M3?

Please check out my new science fiction adventure story now online at http://www.xybears.com. Your help and support with this would be greatly appreciated! Thank you!

Ahh, There is always one in every blog crowd! Forced induction, if managed well by keeping the boost down to 6 P.S.I. or so and perhaps with water injection if necessary is perfectly manageable in a previously normally aspirated car with relatively high compression. But thanks for calling me the nut behind the wheel not knowing a thing about me. And how do you know how well I drive? If only I could go through life so self righteous. Nice to meet you!

As in another post I will ask, why doesn't anybody make a turbo or supercharger kit for the 328? That baffles me.

Because the market has determined that most people that want that power will just get a 335 instead. The companies that develop super/turbochargers probably took the 335 into account and figured there was no point. Who's going to bypass the factory warranty to bump their 328 up to 335 levels and end up spending the same amount?

Quite honestly, I've driven a 328 and loved it. No, it's not as powerful as the crazy 335 but it's smooth, has no HPFP issues and it's pretty damn fast too. Came really close to getting a 6 speed 328i before our 535i. It only had the sport package, xenon lights and heated seats. That's it, no other options. Someone snagged it before we had a chance.

But thanks for calling me the nut behind the wheel not knowing a thing about me.

That expression has been around for a long time, don't take it personally. What he meant was: when you get to the point on the track that the 328i no longer does it for you then you move up in power. My brother-in-law took his 996 Carrera (back around 2001) to the track and he thought he was all that and a bag of chips. Speaking to Rennie Bryant, who was instructing that day, he told me he was stuck behind him for a long time in a stock E36 325i and that the only advantage all the 996's power had was in the straights. My bro-in-law needed to fix the nut behind the wheel first to truly wring out the Porsche to its full potential.

Ahh, There is always one in every blog crowd! Forced induction, if managed well by keeping the boost down to 6 P.S.I. or so and perhaps with water injection if necessary is perfectly manageable in a previously normally aspirated car with relatively high compression. But thanks for calling me the nut behind the wheel not knowing a thing about me. And how do you know how well I drive? If only I could go through life so self righteous. Nice to meet you!

Frankly, I agree with bcweir and eam3.

Why attempt to re-design and "one-up" an entire company full of engineers by modifying a 328, when you can buy a factory-fresh 335 (with 4 year warranty) to do what you HOPE the modified 328 will do (and most likely, at a cheaper price)?

You may indeed be able to accomplish it, but why?

Makes no sense to me.

Now, if there was no 335 available, or if it could be done at a substantial savings over the TRUE cost of a 335, you might have a valid point.

But, maybe that's your thought process....You may think you can do a better job for a lesser price.

Actually that is what I own. An 07 328xi Coupe, sport package, premium package, cold weather package, Logic 7, Dakota leather etc. and I love it! I have decked it out with Beyern wheels, Remus exhaust. I just keep thinking that if I could someday modify it with forced induction two things would happen. 1) Here at high altitude in Colorado it would work much better in the mountains and 2) I wouldn't have to trade it in on a 335!
I'm just a little surprised how little in the way of factory, Dinan and aftermarket mods there are available for the normal aspirated 3 series and what a plethora of mods are available for the turbo models and the M. Seems odd.

I think since 335s are so easily available and not that much more than a 328, the aftermarket companies figured right: not many owners of 328s will be looking to spend the money to bump performance to 335 levels. If they were willing, they would have just bought a 335 in the first place (and again, keep that nice factory warranty)